The aim of this study was to model and optimize the adsorption of Pb(II) ions from an aqueous solution using Africa elemi seed, mucuna shell and oyster shell modified with orthophosphorous acid used as adsorbents. The influence of operational parameters such as adsorbent dosage, initial pH and contact time was evaluated by response surface methodology (RSM). The interactions between the operational parameters were evaluated using Box-Behnken design of response surface methodology. The optimum conditions for maximum removal of Pb(II) ions were observed at pH of 2.0, 100 mg adsorbent dosage and 70 min of contact time, with correlation coefficient R 2 , 0.996 for Africa elemi seed adsorbent; pH of 6.0, 100 mg adsorbent dosage and 40 min contact time with R 2 0.996 for mucuna shell adsorbent; and pH of 6.0, 100 mg adsorbent dosage and contact time of 40 min for oyster shell adsorbent. The ANOVA results obtained from the RSM were analyzed using secondorder polynomial equations, and the contour plots showed the interaction among the variables of the adsorption. This shows that the prepared low-cost adsorbents can be effectively adopted for the removal of Pb(II) ions from industrial wastewaters.

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The aim of this study was to investigate the renal protective properties of aqueous leaf extract of Bryophyllum pinnatum from Nigeria against petrol vapour -induced toxicity on the kidney of male albino rats. Fifty apparently healthy male albino rats aged 8 weeks and weighing between 165 g -185 g were randomly divided into five groups of ten animals each. Group 1 served as control and were not treated with the plant extract or exposed to gasoline vapour. Group 2 served as negative control and were exposed to the gasoline vapour but not treated with the plant extract. Groups 3, 4 EJMP, 19(3): 1-8, 2017; Article no.EJMP.33358 2 and 5 were treated with the plant extract at 20 mg/kg body weight, 40 mg/kg body weight, 60 mg/kg body weight respectively and exposed to the gasoline vapour for 5 hrs daily for 21 days. Results show that mean body weight of treated animals increased significantly (p≤ 0.05) compared to negative control. Haematological parameters; PCV, Hb, Total bilirubin, WBC and RBC increased, while renal function biomarkers Na + , Ca 2+ , Mg 2+ and Cl also increased in the treated animals compared to the negative control respectively. The effect of the plant extract is dose dependent. The results show that the plants extract has renal protective potential on the experimental animals. Original Research Article

This study investigated the utilisation of Luffa cylindrica activated carbon as a low-cost adsorbent in the removal of vanadium(V) from textile industry effluent in a batch adsorption experiment. The adsorption rate was studied for contact time, pH, and adsorbent dosage. The effect of pH on vanadium(V) removal was studied with 0.2 g/100 ml adsorbent dose, 10 min contact time, and textile effluent solution. The maximum removal efficiency was 99.90 % at pH 4, 97.43 % at 60 min of contact time, and 97.83 % at an adsorbent dosage of 1.0 g. The characterisation results from FTIR and SEM indicated that the adsorbents’ potential was fully exploited. In this study, the experimental findings were fitted using Langmuir and Freundlich isotherm models. Freundlich model gave a better fit of the experimental data. The kinetic data by the pseudo-second order kinetic model gave a better fit than the pseudo-first order kinetic model.

The creep and stress relaxation behavior of rice husk reinforced low density polyethylene composite was analyzed in this study. The exponential and power model were used to study the creep while the stress relaxation assessed the time required for the composites to maintain a certain strain level. The creep strain increased with increase in time, at various temperatures, with its highest creep at 70 o C while the lowest is at 30 o C, the power model provided an excellent fit than other models with a coefficient of determination of 0.9977 at 30 o C, the neat low density polyethylene had a good stress relaxation behavior with 4.95 seconds for it to decay and subsequently decreased with increase in filler concentration.